The urban agglomeration of the three northeastern provinces is a huge urban group based on several urban agglomerations. Accelerating the coordinated development of urban agglomerations in Northeast China and optimizing the spatial distribution of population have a great significance to promote a new round of comprehensive revitalization of Northeast China. In the five urban agglomerations of the three northeastern provinces，the number of large cities is small，the population distribution is uneven，and the agglomeration capacity of the population is insufficient，resulting in a wide range of negative population growth. At the same time，there are great differences in the development level among the five urban agglomerations. On the whole，the development level of the two urban agglomerations in Liaoning Province is the highest，the central urban agglomeration in Jilin Province is in the middle，and the development level of the two urban agglomerations in Heilongjiang Province is low. The population of the three provinces continues to gather southward. To optimize the population spatial distribution of northeast urban agglomeration，we need to cultivate core cities in the eastern urban agglomeration of Heilongjiang and node cities in other urban agglomerations，strengthen the coordination and linkage between urban agglomerations，and try our best to retain and attract talents.